U.S. patent number 10,857,339 [Application Number 16/192,430] was granted by the patent office on 2020-12-08 for implantable access port including fluid handling features.
This patent grant is currently assigned to C. R. Bard, Inc.. The grantee listed for this patent is C. R. Bard, Inc.. Invention is credited to Jeremy B. Cox, Elizabeth Richardson, Jason R. Stats.
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United States Patent |
10,857,339 |
Richardson , et al. |
December 8, 2020 |
Implantable access port including fluid handling features
Abstract
An access port for subcutaneous implantation is typically
connected to a catheter, a distal portion of which is disposed
within a vein or other vessel of the patient. The access port
described herein is configured with enhanced fluid handling
features to improve fluid flow therethrough while reducing the
likelihood of clotting or occlusions in the attached catheter, thus
improving system patency. The access port includes a body defining
a reservoir, a needle-penetrable septum covering the top opening of
the reservoir, a stem including a lumen in fluid communication with
the reservoir, and a volume control device positioned in the
reservoir. The volume control device includes a floor designed to
move from a first position below the side opening to a second
position adjacent the bottom surface, and a spring element
positioned between the floor and the bottom surface, the spring
element biasing the floor in the first position.
Inventors: |
Richardson; Elizabeth (Clinton,
MD), Cox; Jeremy B. (Salt Lake City, UT), Stats; Jason
R. (Layton, UT) |
Applicant: |
Name |
City |
State |
Country |
Type |
C. R. Bard, Inc. |
Murray Hill |
NJ |
US |
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Assignee: |
C. R. Bard, Inc. (Franklin
Lakes, NJ)
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Family
ID: |
52105508 |
Appl.
No.: |
16/192,430 |
Filed: |
November 15, 2018 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190083771 A1 |
Mar 21, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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14308962 |
Nov 20, 2018 |
10130803 |
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61837061 |
Jun 19, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M
39/04 (20130101); A61M 39/0208 (20130101); A61M
2039/0226 (20130101) |
Current International
Class: |
A61M
39/02 (20060101); A61M 39/04 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
PCT/US14/43148 filed Jun. 19, 2014 International Search Report and
Written Opinion dated Dec. 22, 2014. cited by applicant .
U.S. Appl. No. 14/308,962, filed Jun. 19, 2014 Advisory Action
dated Aug. 3, 2017. cited by applicant .
U.S. Appl. No. 14/308,962, filed Jun. 19, 2014 Advisory Action
dated May 8, 2018. cited by applicant .
U.S. Appl. No. 14/308,962, filed Jun. 19, 2014 Final Office Action
dated Apr. 19, 2017. cited by applicant .
U.S. Appl. No. 14/308,962, filed Jun. 19, 2014 Non-Final Office
Action dated Dec. 1, 2016. cited by applicant .
U.S. Appl. No. 14/308,962, filed Jun. 19, 2014 Non-Final Office
Action dated Oct. 2, 2017. cited by applicant .
U.S. Appl. No. 14/308,962, filed Jun. 19, 2014 Notice of Allowance
dated Jul. 13, 2018. cited by applicant .
U.S. Appl. No. 14/308,962, filed Jun. 19, 2014 Non-Final Office
Action dated Jun. 3, 2016. cited by applicant.
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Primary Examiner: Mehta; Bhisma
Assistant Examiner: Ponton; James D
Attorney, Agent or Firm: Rutan & Tucker LLP
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. patent application Ser. No.
14/308,962, filed Jun. 19, 2014, now U.S. Pat. No. 10,130,803,
which claims the benefit of U.S. Provisional Patent Application No.
61/837,061, filed Jun. 19, 2013, and titled "Implantable Access
Port Including Fluid Handling Features," each of which is
incorporated herein by reference in its entirety.
Claims
What is claimed is:
1. An implantable access port, comprising: a body defining a
reservoir, the reservoir including: a side wall including a side
opening; a top opening; and a bottom surface; a volume control
device positioned in the reservoir, the volume control device
including: a floor having an outer perimeter configured to provide
a fluid seal against the side wall of the reservoir and a top
surface parallel to the bottom surface of the reservoir, the floor
designed to move from a height-extended first position below the
side opening to a reduced-height second position adjacent the
bottom surface; and a spring element positioned between the floor
and the bottom surface, the spring element biasing the floor in the
height-extended first position, wherein resilient expansion of the
spring element moves the floor from the reduced-height second
position to the height-extended first position to force fluids out
of the reservoir; a needle-penetrable septum covering the top
opening of the reservoir, wherein a first volume of the reservoir
is defined between a bottom of the needle-penetrable septum and the
floor in the height-extended first position prior to insertion of a
needle through the needle-penetrable septum; and a stem including a
lumen in fluid communication with the side opening of the
reservoir.
2. The implantable access port according to claim 1, wherein the
spring element includes a spring washer.
3. The implantable access port according to claim 1, wherein the
spring element includes a coil spring.
4. The implantable access port according to claim 1, wherein at
least one of the body and the floor includes a thermoplastic.
5. The implantable access port according to claim 1, wherein the
reservoir has a second volume greater than the first volume in the
reduced-height second position of the floor.
6. The implantable access port according to claim 5, wherein
movement of the floor from the reduced-height second position to
the height-extended first position pushes fluid out of the
reservoir through the side opening.
7. The implantable access port according to claim 6, wherein the
stem is coupled to a catheter, and wherein movement of the floor
from the reduced-height second position to the height-extended
first position flushes a lumen of the catheter to prevent formation
of clotting.
8. The implantable access port according to claim 1, further
comprising a fluid outlet interposed between the side opening of
the reservoir and the lumen of the stem.
9. The implantable access port according to claim 8, wherein the
fluid outlet includes a top wall, a bottom wall, and opposing first
and second sidewalls.
10. The implantable access port according to claim 9, wherein the
top wall is substantially parallel to the bottom wall, and wherein
the opposing first and second sidewalls taper toward one
another.
11. The implantable access port according to claim 10, wherein the
body includes a base portion and a cap portion, the fluid outlet
defined in the base portion.
12. The implantable access port according to claim 1, wherein the
lumen of the stem defines a proximal lumen portion of a first inner
diameter, the proximal lumen portion positioned in the body, and a
distal lumen portion of a second inner diameter smaller than the
first inner diameter, the distal lumen portion extending outside of
the body.
13. The implantable access port according to claim 12, wherein a
tapered transition region is positioned between the proximal lumen
portion and the distal lumen portion.
14. The implantable access port according to claim 1, wherein the
stem includes a distal portion, the distal portion including a
distal-most portion and a central portion, wherein an outer
diameter of the distal-most portion is larger than an outer
diameter of the central portion.
Description
BRIEF SUMMARY
Briefly summarized, embodiments of the present invention are
directed to an access port for subcutaneous implantation into a
body of a patient. The port is typically subcutaneously connected
to a catheter, a distal portion of which is disposed within a vein
or other vessel of the patient. Percutaneous access to the port via
a needle can enable a clinician to infuse medicaments through the
port and catheter into the vessel of the patient. The port is
configured with enhanced fluid handling features to improve fluid
flow therethrough while reducing the likelihood of clotting or
occlusions in the attached catheter, thus improving system
patency.
In one embodiment, for instance, an implantable access port is
disclosed and comprises a body defining a reservoir, a
needle-penetrable septum covering an opening to the reservoir, a
stem defining an outlet to the reservoir, and a deformable element
included in the reservoir. The deformable element is operably
connected to a main portion of the septum and deforms in response
to displacement of the septum so as to counteract a change in
volume within the reservoir and prevent blood ingress into the
catheter, where it could otherwise clot and occlude the catheter.
Other fluid handling aspects of an access port are also
disclosed.
These and other features of embodiments of the present invention
will become more fully apparent from the following description and
appended claims, or may be learned by the practice of embodiments
of the invention as set forth hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
A more particular description of the present disclosure will be
rendered by reference to specific embodiments thereof that are
illustrated in the appended drawings. It is appreciated that these
drawings depict only typical embodiments of the invention and are
therefore not to be considered limiting of its scope. Example
embodiments of the invention will be described and explained with
additional specificity and detail through the use of the
accompanying drawings in which:
FIG. 1 is a perspective view of an implantable access port
according to one embodiment;
FIGS. 2A and 2B are simplified cross-sectional views of an access
port according to one embodiment;
FIGS. 3A and 3B are various views of a stem of an access port
according to one embodiment;
FIG. 4 is a cross-sectional view of the stem of FIGS. 3A and
3B;
FIG. 5 is a perspective view of a dual-reservoir access port
according to one embodiment;
FIGS. 6A-6C are various cross-sectional views of the access port of
FIG. 5.
FIG. 7 is a cross sectional side view of an access port according
to one embodiment; and
FIGS. 8A and 8B are various cross-sectional views of the access
port of FIG. 7.
DETAILED DESCRIPTION OF SELECTED EMBODIMENTS
Reference will now be made to figures wherein like structures will
be provided with like reference designations. It is understood that
the drawings are diagrammatic and schematic representations of
exemplary embodiments of the present invention, and are neither
limiting nor necessarily drawn to scale.
For clarity it is to be understood that the word "proximal" refers
to a direction relatively closer to a clinician using the device to
be described herein, while the word "distal" refers to a direction
relatively further from the clinician. For example, the end of a
catheter placed within the body of a patient is considered a distal
end of the catheter, while the catheter end remaining outside the
body is a proximal end of the catheter. Also, the words
"including," "has," and "having," as used herein, including the
claims, shall have the same meaning as the word "comprising."
Embodiments of the present invention are generally directed to an
access port for subcutaneous implantation into a body of a patient.
The port is typically subcutaneously connected to a catheter, a
distal portion of which is disposed within a vein or other vessel
of the patient. Percutaneous access to the port via a needle can
enable a clinician to infuse medicaments through the port and
catheter into the vessel of the patient. Likewise, fluids can be
aspirated from the vessel, via the catheter, port, and needle.
In accordance with one embodiment, the port is configured with
enhanced fluid handling features to improve fluid flow therethrough
while reducing the likelihood of clotting or occlusions in the
attached catheter, thus improving system patency. Further details
regarding these enhancements are given below.
Reference is first made to FIG. 1, which depicts an implantable
access port ("port"), generally designated at 10, configured in
accordance with one embodiment. As shown, the port 10 includes a
body 12 that defines a reservoir (FIG. 2A). A compliant,
needle-penetrable septum 14 covers the reservoir and provides
needle access thereto. A stem 16 extends from the port body 12 and
is configured to operably connect to a proximal end of a catheter
that is in turn disposed in the vasculature of a patient. In this
way, vascular access to the patient by a clinician is provided via
the catheter, connected access port, and skin-penetrating needle,
such as an infusion set needle, for instance.
FIGS. 2A and 2B show a simplified, cross sectional view of an
access port similar to the port 10 of FIG. 1. In particular, FIGS.
2A and 2B show the reservoir 26 that is defined by the port body
12, and the manner in which the septum 14 is disposed in a
reservoir opening, or aperture 21, which is defined by the port
body such that the septum covers and isolates the reservoir 26.
In further detail, the septum 14 includes a body 20 and an annular
flange 22 that radially extends from a main portion, or central
portion, 28 of the septum. Note that the main portion as used
herein includes any portion of the septum through which a needle
can penetrate during use of the port, though the size and extent of
the main portion of the septum can vary in other embodiments. The
septum flange 22 is received into an annular groove 32 defined by
the port body 12. The groove 32 is disposed proximate the aperture
21 in the present embodiment, and the fit between the flange 22 and
the groove is such that the septum 14 is secured in place so as to
sealably enclose the reservoir 26. As shown in FIGS. 2A and 2B,
then, the central portion 28 and flange 22 of the septum body 20
extend along a horizontal plane P.
In accordance with the present embodiment, FIGS. 2A and 2B show
that the septum 14 further includes a deformable element, such as a
skirt, or cylindrical extension 24, which extends substantially
perpendicularly from the plane P of the central portion 28 of the
septum body 20. As shown from the perspective of FIGS. 2A and 2B,
the cylindrical extension 24 extends circumferentially downward
from proximate a junction of the central portion 28 and the flange
22 of the septum body 20. As such, a central axis of the
cylindrical extension 24 extends perpendicularly with respect to
the plane P. Note that the location of the cylindrical extension,
as well as its geometric shape, size, thickness, etc., can vary
from what is shown and described herein.
FIG. 2A further shows that the cylindrical extension 24 of the
septum 14 is seated within a correspondingly-sized cylindrical
recess 34 that is circumferentially defined about the periphery of
the reservoir 26. An annular bottom portion of the cylindrical
extension 24 is affixed to a circumferential attachment surface,
which in the present embodiment is defined by a shoulder 36 at the
bottom of the cylindrical recess 34. Such attachment between the
shoulder 36 and the bottom portion of the cylindrical extension 24
can be achieved via mechanical affixation, adhesive, or other
suitable method.
FIG. 2B shows further details regarding operation of the septum 14,
and the cylindrical extension 24 as a deformable element, during
use of the port 10. A hollow needle 38 (such as found in an
infusion set) or other suitable cannula is typically inserted
through the septum central portion 28 such that a distal tip
thereof is disposed within the reservoir 26. In this position, the
needle 38 can infuse fluids into the port reservoir 26, which
fluids then exit the reservoir via the port stem 16 (FIG. 1) and
pass through the attached catheter and into the vein or other
portion of the patient's vasculature. Once infusion is complete,
the needle 38 is removed from the septum central portion 28 by
exerting an upward pulling force thereon. Because the septum 14 is
made from a compliant compressible material, such as silicone in
one embodiment, pulling of the needle from the septum 14 causes the
central portion 28 of the septum to deform, or be displaced, in a
vertically upward direction due to compressive friction between the
needle and the septum. An example amount of deformation caused by
such needle removal can be seen by the upward deformation of a
bottom surface 28A of the central portion 28 of the septum in FIG.
2B as the needle 38 is withdrawn upward.
Without some form of compensation, the above-described deformation
of the central portion 28 of the septum 14 as shown in FIG. 2B
causes a temporary increase in volume of the reservoir 26. If left
unchecked, the increase in reservoir volume can in turn produce a
vacuum force within the reservoir. Production of the vacuum force
within the reservoir can cause blood from the vein to be aspirated
a short distance into the distal end of the catheter lumen, where
it can clot, thus undesirably occluding the catheter.
In accordance with one embodiment, the cylindrical extension 24 of
the septum 14 is configured to compensate for the above effects
caused by removal of the needle 38 from the septum. In particular,
the cylindrical extension 24 of the septum 14 serves in the present
embodiment as a compensation portion to compensate for and negate
the increase in reservoir volume and the consequent production of
vacuum force within the reservoir 26. It is noted that the
cylindrical extension 24 operates, as described below, about a
pivot 39 that is established by the securement of: 1) the flange 22
of the septum body 20 in the port body groove 32; and 2) the bottom
portion of the cylindrical extension 24 to the shoulder 36. So
configured, the pivot 39 is a loop defined annularly about an upper
portion of the cylindrical extension 24, though it is appreciated
that the particular shape and location of the pivot 39 can vary
according to desired cylindrical extension flexing, size and
configuration of the septum, etc.
The above-described securement of the cylindrical extension 24 and
the corresponding pivot 39 enables the cylindrical extension--which
as described in the present embodiment includes compliant silicone
and is integrally formed with the septum central portion 28--to
compliantly and laterally move, i.e., bulge, or flex, radially
inward toward the center of the reservoir 26 in response to the
upward deformation of the septum central portion 28 described
above. The degree of flexing of the cylindrical extension 24 in one
embodiment is shown in FIG. 2B, wherein an inner surface 24A of the
cylindrical extension bulges radially inward. The inward flexing of
the cylindrical extension 24 of the septum 14 reduces the volume of
the reservoir 26, thus compensating for the increased reservoir
volume caused by the septum central portion displacement. The net
result is that the volume of the reservoir 26 remains substantially
constant during needle withdrawal from the septum 14, and no vacuum
force is created therein. Thus, no aspiration of blood into the
distal tip of the catheter occurs, and the catheter lumen remains
patent.
Note that the reservoir in the illustrated embodiment defines an
annular cavity 37 about the interior side surface of the reservoir
adjacent to the cylindrical extension so as to encourage separation
of the cylindrical extension from a side surface of the reservoir.
Though shown in cross section here as semi-circular, the annular
cavity 37 can define other shapes, including square, triangular,
etc., and can be positioned in different locations within the
reservoir and include different sizes, etc. In yet another
embodiment, no annular cavity is included within the reservoir.
Once the needle has been fully retracted from the central portion
28 of the septum 14, the central portion resiliently returns to its
original shape, as shown in FIG. 2A, thus causing the cylindrical
extension 24 of the septum to pivot back to its original, un-flexed
configuration, also shown in FIG. 2A.
Note that, though they are integrally formed here, in one
embodiment the cylindrical extension and septum are separate
components but operably mated such that deformation of the central
portion of the septum causes the cylindrical extension to
correspondingly flex or move to compensate for the change in
reservoir volume. Also, in one embodiment the cylindrical extension
can include two or more pieces that do not fully encircle reservoir
but nonetheless flex inward a sufficient amount to compensate for
the deformation of the septum central portion. In addition, the
septum can be formed of other resilient materials in addition to
silicone. Note that, in one embodiment, the amount of cylindrical
extension deformation is proportional to the amount of septum
central portion displacement, given the pivoting action described
herein.
FIGS. 3A-4 are various views of the stem 16 of the port 10
according to one embodiment. As shown, the stem 16 includes a body
40 extending between a proximal end 40A that is inserted into a
hole defined in the body 12 of the port 10 and a distal end 40B
that is configured to mate with a proximal end of a subcutaneously
placed catheter. The stem body 40 defines a fluid conduit 46 that
enables fluid to travel from the port reservoir 26 to a lumen of
the catheter.
In greater detail, the fluid conduit 46 defines a proximal portion
42 extending distally from the proximal end 40A of the stem body 40
and a distal portion 44 extending proximally from the distal end
40B (FIG. 3B). In contrast with other stem designs, in the present
embodiment the fluid conduit 46 defines a varying diameter
configuration, wherein the proximal portion defines a relatively
wide first inner diameter ID1 proximate the proximal end 40A of the
stem body 40, as shown in FIG. 4. The first inner diameter ID1
reduces via a tapered transition region 48 to a second inner
diameter ID2, which diameter extends through the distal portion 44
of the fluid conduit 46. The second inner diameter ID2 is sized in
the present embodiment to enable fluid to be passed into the
subcutaneous catheter attached over the distal end 40B of the stem
16 when the port 10 is disposed within the body of the patient.
The gradual transition in inner diameter from large (ID1) to
relatively small (ID2) as described above in connection with FIG. 4
assists in reducing fluid pressure through the stem 16. This in
turn improves flow characteristics and opens up options for port,
stem, and catheter design. Note that, though here shown as having a
gradual taper of a certain radius and length, the transition region
48 of the stem fluid conduit 46 can define other gradually changing
cross-sectional shapes. Further, the relative sizes of the first
and second inner diameters can vary from what is shown and
described.
FIGS. 5-6C show details of a dual-reservoir port 50 according to
one embodiment. The port 50 includes a body 52 and two septa 54
each attached so as to cover an aperture of a respective reservoir
58. A stem 56 including a fluid conduit 68 for each of the
reservoirs 58 is also included.
As best seen in FIGS. 6A and 6B, a fluid outlet 60 is interposed
between each of the reservoirs 58 and the corresponding fluid
conduits 68 of the stem 56. In accordance with the present
embodiment and in contrast with known designs, the fluid outlets 60
are tapered approaching each fluid conduit 68. In particular, each
tapered fluid outlet 60 includes two side walls 62 that converge in
a tapered fashion from the reservoir 58 toward a conduit entrance
68A of the respective stem fluid conduit 68. In addition, each
fluid outlet 60 includes a floor 64 and a top wall 66, as best seen
in the cross-sectional views of FIGS. 6B and 6C, which also
converge in tapered fashion toward the respective conduit entrance
68A. In other embodiments it is appreciated that the floor, top
wall, and side walls can have other positional relationships to one
another, such as a tapering together of only the floor and top
walls instead of the tapering of all walls, etc.
The above-described fluid pathway design assists in desirably
reducing fluid pressures between the reservoirs 58 and the
subcutaneous catheter connected to the distal end of the stem 56,
compared to fluid outlet designs where the transition from the
reservoir to the fluid conduit is relatively abrupt. Note that the
particular degree of taper and size of the fluid outlets can be
modified from what is shown and described herein while still
residing within the principles of the present invention. Also,
access ports of various configurations can benefit from the tapered
fluid outlets described herein, including single-reservoir ports
and ports with more than two reservoirs. In another embodiment, the
tapered fluid outlets include a round cross section or other
geometric shape.
FIGS. 7-8B depict various details regarding an access port
according to one embodiment, as shown, the port 10 includes a body
12 that captures a septum 14 that covers a reservoir 26. A stem 16
defining a fluid conduit 17 for the reservoir 26 is also included.
As shown in FIG. 7, a movable floor 72 is disposed within the
reservoir 26 in such a way as to be substantially parallel to a
base 70 of the reservoir and to extend across the two-dimensional
dimensions of the reservoir. For instance, in the case of the
reservoir 26 including a round base 70, the floor 72 also defines a
round two-dimensional shape. Of course, other reservoir and floor
two-dimensional shapes are possible. The floor 72 can include a
suitable material, such as metal, thermoplastic, etc.
A spring element 74 is interposed between the reservoir base 70 and
the movable floor 72 to urge the floor into a height-extended first
position, as seen in FIG. 7. The spring element 74 can include a
spring washer, such as a Belleville washer or cupped spring washer,
or other suitable element to provide a compliant urging force in
the upward direction (from the perspective shown in FIG. 7) to
maintain the floor in the first position of FIG. 7. In the first
position, the floor 72 causes the reservoir 26 to define a first
volume.
The spring element 74 is compressible to enable the floor 72 to be
depressed into a reduced-height second position, shown in FIG. 8A.
The floor 72 can be depressed by a needle 80 that is inserted
through the septum 14 of the subcutaneously placed port 10. Such
insertion of the needle 80 through the septum 14 and into contact
with the floor 72 causes the floor to press on and compress the
spring element 74 such that the floor moves into the reduced-height
second position of FIG. 8A. With the floor 72 in this position, the
reservoir 26 defines a second volume that is greater relative the
first volume when the floor is in the first position. In this
position, medicaments or other fluids can be injected through the
reservoir 26 of the port 10 via the needle 80 for passage through
the subcutaneous catheter attached to the stem 16. Similarly,
fluids may be aspirated by the needle 80 from the catheter via the
reservoir 26.
Once use of the port 10 is complete, the needle 80 can be removed
from the septum 14. Removal of the needle 80 also removes the
downward force provided thereby on the floor 72, which enables the
spring element 74 to resiliently expand, causing the floor to rise
from the reduced-height second position (FIG. 8A) back to the
initial height-extended first position shown in FIG. 8B. This
upward movement of the floor 72 reduces the volume of the reservoir
26 from the second volume (FIG. 8A) to the relatively smaller first
volume (FIGS. 7, 8B). Such reduction of reservoir volume forces
fluids still present in the reservoir 26 to escape out the conduit
17 of the stem 16 and through the catheter attached thereto, also
referred to as a "positive flush." As a result, any blood or body
fluid present in the catheter is flushed out of the catheter, thus
preventing the undesired formation of blood clotting within the
lumen of the catheter.
Note that other types of springs and resilient components can be
employed for the spring element, and such components can vary in
size, number, placement, etc. For instance, more than one
Belleville washer can be disposed beneath the floor of the
reservoir, in one embodiment. These and other variations are
therefore contemplated.
Embodiments of the invention may be embodied in other specific
forms without departing from the spirit of the present disclosure.
The described embodiments are to be considered in all respects only
as illustrative, not restrictive. The scope of the embodiments is,
therefore, indicated by the appended claims rather than by the
foregoing description. All changes that come within the meaning and
range of equivalency of the claims are to be embraced within their
scope.
* * * * *